A linear motion guide apparatus as disclosed in Patent Literature 1 has been known as a related-art apparatus that is available as a support and guide device of this type. This linear motion guide apparatus includes track rails along which rolling surfaces for a large number of rolling elements are formed, and moving blocks mounted to those track rails through intermediation of the rolling elements. The rolling elements are configured to roll on the rolling surfaces of the track rails while bearing loads so that the moving blocks are freely movable along the track rails. Depending on a size or a weight of the movable body such as tables and units to be guided, in general, the track rails are arranged parallel to each other in two rows, and the plurality of moving blocks to be moved along those track rails are fixed to the movable body. With this, the movable body can be moved with high accuracy along the track rails.
This linear motion guide apparatus is utilized mainly for linear guide along an X-axis, a Y-axis, and a Z-axis in working machines so that objects-to-be-conveyed such as workpieces and tools are guided and positioned with high accuracy. Requests for guiding the objects-to-be-conveyed with high accuracy cannot necessarily be satisfied due to a limitation on a length of the track rails to be manufactured. Thus, when a moving distance necessary for the objects-to-be-conveyed is larger than a length of a single track rail, the plurality of track rails are coupled in series to each other without clearances so as to form guide tracks having a length corresponding to the moving distance of the objects-to-be-conveyed. With this configuration, the moving blocks are movable over an entire length of the guide tracks across joints between the track rails. Further, the rolling surfaces are formed through a collective grinding process so as to suppress height differences among the joints between the plurality of track rails to be arranged in series. In this way, dimensions are strictly managed. With this, the objects-to-be-conveyed can be guided with high accuracy along the guide tracks formed by coupling the plurality of track rails to each other.